Use of gene tests to detect hereditary predisposition to cancer: what do we know about cost effectiveness?

Mutations in 4 genes associated with DNA repair have been shown to be associated with hereditary non-polyposis colon cancer (HNPCC) in families which display unusually high risk for colorectal cancer. Laboratory tests for mutations in these genes will soon be commercially available, raising the possibility that population-wide gene testing to identify individuals with an inherited susceptibility to colorectal cancer could be conducted. The purpose of our report is to explore the economic implications of conducting a program of population-wide screening for HNPCC compared with alternative programs which would be restricted to families already known to be at high risk for HNPCC. Rather than provide a definitive answer to these questions, our purpose is to indicate priority areas of research which need to be conducted before such a definitive analysis can be done. An exploratory analysis has been conducted to determine which factors are most important in determining the cost-effectiveness of a genetic testing program for HNPCC. The base case analysis focuses on current uncertainty about the population prevalence of the HNPCC genotype and phenotype, factors which are central to the cost-effectiveness of population-wide screening. Uncertainty in parameters related to the cost and effectiveness of screening and preventive interventions for HNPCC were explored using additional sensitivity analyses. Favorable levels of cost-effectiveness for population-wide screening are achieved only when the most favorable assumptions about HNPCC prevalence and the cost and effectiveness of screening and preventive interventions are made.